This invention relates to the mounting of brake discs on a pilot rib of a shaft and especially to brake discs which are subject to high temperatures causing thermal shrinkage. Such shrinkage makes removal of the brake disc difficult and may cause distortion of the discs. In the past devices have been proposed to prevent binding of the disc on the shaft; however, they have necessitated extensive machining of the disc to build in deformability through a thin wall section. Because the material of the disc is of high strength steel, the thickness of the thin walls and the radial width have been critical dimensions requiring close tolerances and added expense of manufacture. In order to avoid this problem, a thin walled ring of softer metal than the disc metal has been mounted on the disc; however, obtaining the accurate registry with a thin edge of soft material has been difficult because of the tendency of the thin walled member to bend during manufacture and installation.